Substitution method of at least one portion of a video stream and video receiver implementing the method

Abstract

The disclosure relates to a method for substituting a multimedia sequence in a multimedia stream, the method comprising: receiving by a multimedia receiver, a first multimedia stream; transmitting the first multimedia stream to a decoder of the multimedia receiver; at a first instant, interrupting the transmission of said first multimedia stream to the decoder, and transmitting a second multimedia steam to the decoder; and at a second instant, stopping the transmission of said second multimedia stream to the decoder, and resuming the transmission of the first multimedia stream to the decoder, from a part of said first multimedia stream having a timestamp corresponding to said second instant.

1 . A method for substituting at least one portion of a multimedia stream, the method comprising:
 receiving by a multimedia receiver, a first multimedia stream;   transmitting the first multimedia stream to a decoder of the multimedia receiver;   generating a control signal for controlling a switching module configured to transmit either said first multimedia stream or at least a second multimedia steam to a demultiplexer of the feeding a decoder, said demultiplexer and said decoder being embedded in said multimedia,   the reception of the controlling signal by switching module triggering:   at a first instant indicated in said controlling signal, an interruption of the transmission of said first multimedia stream to the demultiplexer, and a transmission of said second multimedia steam to the demultiplexer; and   at a second instant indicated in said controlling signal, a stopping of the transmission of said second multimedia stream to the demultiplexer, and a resuming of the transmission of the first multimedia stream to the demultiplexer, from a part of said first multimedia stream having a timestamp corresponding to said second instant.   
     
     
         2 . The method of  claim 1 , further comprising receiving, by the multimedia receiver, substitution duration data specifying the first instant and the second instant in a time base of the first multimedia stream. 
     
     
         3 . The method of  claim 1 , wherein the first multimedia stream has at least one of the following features:
 the first multimedia stream is a live multimedia stream,   the first multimedia stream comprises an audio and/or a video stream, and   the first multimedia stream comprises a video stream in a standard definition, a high definition, or an ultra-high definition.   
     
     
         4 . The method of  claim 1 , wherein the time data are received in a file containing a network address of a server storing the substitution multimedia stream. 
     
     
         5 . The method of  claim 1 , wherein the first multimedia stream being encrypted, the method further comprising:
 receiving entitlement messages including decryption keys for decrypting the first multimedia stream, each decryption key having a respective validity period;   extracting the decryption keys from the entitlement messages;   decrypting the first multimedia stream using the decryption keys and taking into account a time base of the first multimedia stream with respect to the validity periods of the decryption keys, before decoding the first multimedia stream; and   during the decoding of the second multimedia stream, continuing to receive the entitlement messages of the first multimedia stream and extract the decryption keys.   
     
     
         6 . The method of  claim 1 , further comprising receiving, by the multimedia receiver, substitution duration data comprising one of the following data:
 a duration of the portion of the first multimedia in the first multimedia stream to be substituted,   a timestamp of a last multimedia packet of the portion of the first multimedia in the first multimedia stream to be substituted, and   a timestamp of a first multimedia packet of the first multimedia stream to be decoded and following the stopping of the decoding of said second multimedia stream.   
     
     
         7 . The method of  claim 1 , further comprising resetting audio and video decoders before transitions between the first multimedia stream and the second multimedia stream. 
     
     
         8 . A multimedia receiver comprising a demultiplexer feeding a decoder, a switching module to transmit either a first multimedia stream or at least a second multimedia to said demultiplexer and at least one processor configured to:
 receive said first multimedia stream;   transmit the first multimedia stream to said decoder;   generate a control signal for controlling the switching module,   transmit said controlling signal to the switching module, the reception of said controlling signal by the switching module triggering:   at a first instant indicated in said controlling signal, an interruption of the transmission of said first multimedia stream to the demultiplexer, and a transmission of said second multimedia steam to the demultiplexer; and   at a second instant indicated in said controlling signal, a stopping of the transmission of said second multimedia stream to the demultiplexer, and a resuming of the transmission of the first multimedia stream to the demultiplexer, from a part of said first multimedia stream having a timestamp corresponding to said second instant.   
     
     
         9 . The receiver of  claim 8 , further configured to:
 receive time data specifying the first instant and the second instant in a time base of the first multimedia stream.   
     
     
         10 . The receiver of  claim 8 , wherein the first multimedia stream being encrypted, the receiver is further configured to:
 receive entitlement messages including decryption keys for decrypting the first multimedia stream, each decryption key having a respective validity period,   extract the decryption keys from the entitlement messages;   decrypt the first multimedia stream using the decryption keys and taking into account a time base of the first multimedia stream with respect to the validity periods of the decryption keys, before decoding the first multimedia stream, and   during the decoding of the second multimedia stream, continue to receive the entitlement messages of the first multimedia stream and extract the decryption keys.   
     
     
         11 . A non-transitory computer readable medium comprising code portions which, when loaded into an internal memory and executed by a computer, configure the computer to carry out the steps of:
 receiving by multimedia receiver, a first multimedia stream;   transmitting the first multimedia stream to a decoder of the multimedia receiver;   generating a control signal for controlling a switching module configured to transmit either said first multimedia stream or at least a second multimedia steam to a demultiplexer of the feeding a decoder, said demultiplexer and said decoder being embedded in said multimedia,   the reception of the controlling signal by the switching module triggering:   at a first instant indicated in said controlling signal, an interruptioning of the transmission of said first multimedia stream to the demultiplexer and a transmission of said transmitting a second multimedia steam to the demultiplexer; and   at a second at indicated in said controlling signal, a stopping of the transmission of said second multimedia stream to the demultiplexer, and a resuming of the transmission of the first multimedia stream to the demultiplexer, from a part of said first multimedia stream having a timestamp corresponding to said second instant.